Effects of PEG on the stability and electrochemical properties of PEDOT: PSS films obtained by spin coating

By mixing the same concentration polyethylene glycol (PEG) with molar masses of 400, 600 and 1000, a series of poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT: PSS) composite thin films were prepared by spin coating. The morphology of the films was inspected by Atomic Force Microscopy (AFM). Electrochemical characterizations performed over a time span of five days including Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) were used to determine the stability of the films. The experimental results showed that the properties of PEDOT: PSS films were greatly influenced by the molecular weight of PEG.